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28 Mar 2024 | 12:48 PM UTC

Brazil: Elevated dengue fever activity reported in multiple areas, especially Distrito Federal, in March /update 4

Elevated dengue fever activity reported in multiple areas in Brazil, especially Distrito Federal, in March. Avoid mosquito bites.

Warning

Health authorities have reported elevated dengue fever activity in multiple areas in Brazil, with an additional 1,284,675 cases reported March 2-27, bringing the total case count to 2,323,150 cases (1,144.1 cases per 100,000 population at risk) since Jan. 1. This is compared to the 489,954 cases reported over a similar period in 2023. Distrito Federal is most at risk, reporting 6,337.5 cases per 100,000 population at risk. States reporting more than 1,000 cases per 100,000 population at risk include Minas Gerias (3,725.6 cases per 100,000 population), Espirito Santo (2,242 cases per 100,000 population), Parana (1,924.2 cases per 100,000 population), Goias (1,742.1 cases per 100,000 population), Santa Catarina (1,073.6 cases per 100,000 population), Sao Paulo (1,043.8 cases per 100,000 population), and Rio de Janeiro (1,022.1 cases per 100,000 population). Health officials have distributed dengue vaccines to affected states, and are urging the public to take necessary disease prevention measures, including clearing any standing water, eliminating mosquito breeding sites, avoiding mosquito bites, and seeking medical attention if they are experiencing any symptoms. This report represents the most complete data available as of March 28.

If you have previously been infected with dengue fever, consult with your physician regarding vaccination. Avoid mosquito bites and remove standing water to reduce the number of biting mosquitoes. Seek medical attention if symptoms develop within two weeks of being in affected areas. Do not use aspirin or ibuprofen products if dengue fever is suspected, as these could exacerbate bleeding tendencies associated with the disease.

The risk of dengue fever infection exists year-round nationwide in Brazil, with increased risk in urban and semi-urban areas. Parts of Brazil experience dengue fever transmission year-round, but the highest number of cases historically occur January-June during the rainy season. Brazilian health authorities reported roughly 3,028,590 dengue fever cases nationwide in 2023, 2,363,490 cases in 2022, 975,474 cases in 2021, and 1,467,142 cases in 2020.

There are two dengue fever vaccines, Dengvaxia and Qdenga. It is only recommended for individuals with a history of dengue infection and in a country with a high dengue fever burden. Dengue fever is transmitted through the bite of an infected mosquito. The risk of infection is often highest in urban and semi-urban areas. Symptoms of dengue fever include a sudden onset of fever and at least one of the following: severe headache, severe pain behind the eyes, muscle and/or joint pain, rash, easy bruising, and/or nose or gum bleeding. Symptoms typically appear 5-7 days after being bitten but can develop up to 10 days after exposure. Dengue fever can progress to a more severe form known as dengue hemorrhagic fever (DHF). DHF can be fatal if it is not recognized and treated in a timely manner.